all get proper answers.
But when I run
rails new blog,
I get the following error message:

/usr/local/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in `require': no such file to load -- openssl (LoadError)

Below is the full trace:
run bundle install
/usr/local/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in require': no such file to load -- openssl (LoadError)
from /usr/local/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:inrequire'
from /usr/local/lib/ruby/1.9.1/net/https.rb:92:in <top (required)>'
from /usr/local/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:inrequire'
from /usr/local/lib/ruby/site_ruby/1.9.1/rubygems/custom_require.rb:36:in require'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/vendor/net/http/persistent.rb:447:inssl'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/vendor/net/http/persistent.rb:216:in connection_for'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/vendor/net/http/persistent.rb:358:inrequest'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/fetcher.rb:135:in fetch'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/fetcher.rb:163:infetch_dependency_remote_specs'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/fetcher.rb:122:in fetch_remote_specs'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/fetcher.rb:70:inspecs'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/source.rb:234:in block in remote_specs'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/source.rb:232:ineach'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/source.rb:232:in remote_specs'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/source.rb:165:infetch_specs'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/source.rb:70:in specs'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/definition.rb:205:inblock (2 levels) in index'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/definition.rb:202:in each'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/definition.rb:202:inblock in index'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/index.rb:9:in build'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/definition.rb:198:inindex'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/definition.rb:192:in resolve'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/definition.rb:127:inspecs'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/definition.rb:122:in resolve_remotely!'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/installer.rb:48:inrun'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/installer.rb:12:in install'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/cli.rb:220:ininstall'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/vendor/thor/task.rb:22:in run'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/vendor/thor/invocation.rb:118:ininvoke_task'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/vendor/thor.rb:263:in dispatch'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/lib/bundler/vendor/thor/base.rb:386:instart'
from /usr/local/lib/ruby/gems/1.9.1/gems/bundler-1.1.3/bin/bundle:13:in